Variable load brake



I April 17, 1945- H..|. TRAMBLIE 2,374,053

VARIABL LOAD BRAKE I I Filed Feb. 27, 1943 2 Sheets-Sheet ,1

April 17, 1945. H. l. TRAMBLlE 2,374,053

VARIABLEl LOAD BRAKE Filed Feb. 27. 194:15v 2 sheets-sheet 2 INVENTOR HARRY I TFAMBLIE AEw I www ATTORNEY Patented Apr. 17, 1945 UNITED STATES PATENT oFFlC'E Harry I. Tramblcgurora, Westinghouse Air Brake Company, y Pa., a corporation of Pen Ill.,v assignor to The Wilmerding, nsylyania 4 f Application Februaryy 27, 194s, seria1fN0.477,ss4

This invention relates l'to'rallway rigging and more particularly to variable load brake rigging of the type: in which the leverage thereof maybe automatically varied in accordance with variations in the weight of the load on the vehicle to correspondingly vary theforce with Which the brake may be applied. An object of the invention is to provide an im proved variable load brake apparatus of the above mentioned type, including novel means for effecting the adjustment of the rigging to provide the braking action called for by the weight carried by the vehicle.

Other objects and advantages will appear in the following detailed description of the invention. .I

In the accompanying drawings Fig. 1 is a vertical sectional view taken longitudinally of a, railway vehicle truck to illustrate the adjusting element and the parts of the truck with which they are associated.

Fig. 2 is a plan view of a vehicletruck embody'- ing the adjusting elements and associated parts illustrated in Fig. 1.

Fig. 3 is a sectio al view taken on the line 3 3 to Fig, 1.

As shown in the accompanying draWings,`-the i adjacent theilongitudinal variable load brake apparatus is applied to a railway vehicle truck which may be of the usual well having va truck bolster I which are rigidlyv known construction laterally spaced side frames 2 carried in the usual manner by the wheel -and axle assemblies 3 and a spring plank 4 which is fixed'tothe truck side frames and upon which the usual truckv bolster supporting springs (not shown) seat.

The variable load brake apparatus may comprise two brake cylinder devices 5, one of wh-ich` is disposed adjacent each side frame 2. Each brake cylinder device is provided with a cylinder 6 which is rigidly secured in any suitable manner to a bracket 1 which preferably extends'transversely of the truck and is rigidly secured at each end to one of the side frames 2. Each cylinder contains the usual piston (not shown)` having a push rod 8 which is operatively connected at its outer end, by means of a pin l0, to the upper end of a brake cylinder lever arm Il which exleverll at its opposite or lower end is operar one end lin la bracket I34 11 claims. (o1. 18s- 195) vehicle brake 3 in a direction toward the of the truck. At the end center line of thetruck each shaft I2 is rotatably vmounted in a, bearing member I5 carried by the spring plank 4. f

operatively connected to each shaft I 2` at-the end adjacent each'bracket I3 is a lever' arm I1. As best shown in Fig. 1, the arm I1, at each side of thetruck, extends at substantially right angles `from each Abracket I longitudinal center line to the'arm II and projects into the space betweenthe lower or under side of the truck bolster l and the upper or top side of the spring plank 4; Each arm I1, at its outer end is provided with a jaw I8 having a slotted opening. I9 which extends longitudinally of the armg' `Rigidly attached to and projecting downwardly from the under side 'of the spring plank 4 at each side of the truck' is a bracket 20. Pivotally connected tov each bracket, Vby'means of a pin 2l is one end'of'an upwardly extending substantially vertically disposed member 23, whichfmember passes through the jaw I 8=of the arm I7.

f The upper end of each member -is provided with a slotted opening 25 which extends longitudinally endof` the. slotted opening I9 in the arm I1.

Each member 2351s also provided at one side thereof with a projection 28 having a downwardly and outwardly sloping surface 29 which is engaged. by a-roller 3II.` l'I'he roller 30 at each side of the truck is'carried by a bracket 3|. rigidly attached to andr projecting downwardly from the under side of the-bolster.

f the bolster and extend longitudinally thereof 55 Contained in the'slotted openings the arm'y I1 and member 23, respectively, at each side of the truck is a pin 32 which is carried by the 'lower ends of a pair of substantially vertik cally disposed rods 33 and 34, respectively, which are arranged one at each side of the jaw I8. Therods'33 and 34 at each side of the truck extend'upwardly through suitable openings provided in the bolster to a point above the side frame 2 and each is connected at its upper end to one end of ay brake applying lever 36 by means of a `pin 31.

'The brake applying levers 36 extend longitudinally of the truck and are arranged one at each side of the' transverse center line of the truck.

'i Pivotally connected to the outer end of each brake` applying lever 'is a brake shoe head 40 to which is' lsecured av brake shoe of the usual well .knowntype which' is adapted to be moved, through the medium ofthe ofengagement' withv the tread lof the adjacent I9 and 25 of head, into and outy inthei slotted opening Operation j Assuming the vehicle embodyingy the invention to be empty be in the position illustrated in the drawings, andconsequently will be in condition for' empty braking.

Since the brake cylinder device 5 at each side of. the truck'. and. the mechanism associated with each are substantially identical it will be deemed suilicientA for the purpose of this specincation to' describe the. operation of one brake cylinder. device and the mechanism associated therewith. i When it is desired to effect. application of the brakes, duid. under; pressurel isl supplied to the? brake cylinder: device in. the usual. manner by way of. a; pipe: Fluid under pressureV thus supplied? to 'the brake'l cylinder devicesv causes the usual piston. thereot (not shown) tof operate to moveltbe push rod 8 irr a direction toward the right hand from'. che position. in which it is shown in the drawings.. this direction 'rt causes. the c-zormected?V brake cylinder.l lever' arm. tl shaft lf2: and. arm- H to rock` in a clockwise direction.. The armY Il as itis thus rocked in this direction. acts through the medium of. pinv 32. to forcel the: rods 33 and. 3c upwardly,l the pin 32 moving;` upwardly in the slottedv opening 25Y provided i-n the member The rods 33 and 34 as they are thus moved cause the connected ybrake applying levers, 36 toi rock. about; the rods.` M and move: the brake shoes associated with the levers intoV frictional engagement withther treads of the adjacent wheels to effect' an; application of thebrakes.

When. itis desired to effect a release of the brakes fluid under pressure is vented from'. the .fr to. the atmospherey by way of. pi'pe 5v` irr the' usual well known. manner. As the pressure of uid in the" brake' cylinderY reduces due to such venting, the usual brake cylinder release spring (not shown)` acts on the brake cylinderpiston to.cause thepush rod 8 to move in. a direction toward the lett hand.- to the position; in which it is shown in the drawings..

The push rod. 8, as: it is thus moved, causes the arm H, shaft l2. and arm' i1' to rock in a counterhclockwise direction thereby pulling the rods 33 and 34 downwardly, thev pin 32 moving 25 inthe member 23.

The. rods 33 and 34. as they are. thus moved cause the brake applying levers E36 to rock about the rods' 4f to move the brake shoes outor frictional engagement withthe treads of the adjacent` wheels to effect a release: of the. brakes.

Assuming now that, are released, lading placed orr the body of the vehicle; Under the niiuencef' of the additional weight which the lading imposes onA the ve hicle body and thereby' the' truck bolster, the bolster springs (not shown)l 'will yield. and: per'- and the .brakes on thevehi'clej re,` leased, the several parts of the apparatuswill` As the-^ push rod & moves in z while the vehicle brakes mit the bolster and the body of the vehicle to move downwardly relative to the spring plank 4.

As the bolster l moves downwardly relative to the spring plank 4, the bracket 3i and roller 3D carried by the bolster is caused to move in the same direction. Since roller 30 engages surface 29 of the member 23, the roller will, as it moves downwardly,l clockwise direction about thepivot pin 2l. As the member 213 rocks in this direction the pin 32 is caused to move in the slotted opening i9 of the arm l1 in a direction toward the shaft i2,

thus'. shortening the effective length of the arm and thereby increasing the power of the rigging, If the pin 32. and thereby the rods 33 and Mare moved in the slotted opening I9 of the arm Il in a direction away the leverage ratio, of the rigging will be decreased.

From this it will be understood that the distance between the shaft l2=y and the pin 32. is automatically varied. according tothe load'. on the vehicle as determinedV by the degree of truck spring. compression. to provide for the de.- gree eli4 braking called for by' the weight of the ladingfcarried by: the. vehicle.

When the loading.' of the vehicle is completed, the pin 321wi11.- be positioned relative to the shaft l2( in accordance' with. the. weight carried by the vehicle. Now when1 it is, desired to effect an application. of theY brakesfluid undery pressure is again supplied to the brake cylinder causing the push rod 8 to move outwardly and actuate the brake shoes intoV engagement with the treads of the adjacent. wheels in .the same mannerr as hereinbefore described in connection with empty vehicle braking.

When it is desired to effect a subsequent release of the' brakes after an application has been eiected on. either a. partially or fully loaded vehicle, fluid under pressure is. released fromY the brake cylinder in the usual. manner and the brakes are releasedin. the same manner as hereinbefore described in connection with a releasey of. the brakes following an. application on an empty vehicle.

Having; now described my invention," wha-t- I claim as new and desire to secure by Letters Patent.is: j

le. Irr a. variable4 load brake. rigging for a vehicle truck having a relatively stationary part carried by the truck wheels and also having a partm'ovable vertically' relative tothe stationary part, in. combination; a. brake. element movable into and out of brakingv engagement withv one of the wheels of the truck, a lever carried by the stationary part of thel truck operative 'for actuating said brake element, a member movable vertically for. operating said lever, an arm pivotally carried by a stationary part of the truck for actuating said member,|means operative to actuate sid arm, and means including a roller member carried by' a. movable part of. the truck and a pivotally mounted member carriedv by a; stationary part of the truck operative in response to relative verticalmovement between the stationary and the movable parts oiV the truck for varying the eilectivelength of said 2. In a variable load brake-V rigging forf a vehicl'e truck having a relatively stationary part carried by the truck wheels and. also having a part movable vertically relative to the stationary part, in combination, a. brake element movable into and out of braking" engagement with one cause the member 23 to rock in a from the shaft I2 stationarypart ofthe truck operative for actu# ating said brake element, a member movable vertically for operating said lever, an arm pivotally carried by a stationary part of the truck for actuating' said member, means oper-l ative to actuate said arm, means pivotally-carried by a stationary part of the truck operative to vary the effective length of said arm, and a roller carried by a .movable part of the truck adapted to operate the second mentioned means in response' to relative vertical movement vbetween'the stationary and movable partsof the truck. i y

3. Ina variable load brake rigging fora vehicle truck having a relatively stationary part carried by the truck Wheels and alsohaving. a part movable vertically relative to the stationary part, in combination, a brake element movable' into and out of braking engagement with one of the wheels of the truck, a lever carried' -by the stationary part of the truck operative for actuate ing said brake element, a member movable ver#` tically for operating said lever, ank arm pivotally carried by va stationary part of the truck for acr tuating said member, means Aoperative to actuateg said arm, vertically disposed means pivotally ycarried by a stationary part of the truck and operative to vary the effective length of said arm, said vertically disposed means having at one side thereofA an outwardly and downwardly sloping surface, a'froller carried byav movable part of the truck and engaging said surface, said roller being operative n response to vertical movement of the movable part of the truck for actuating said vertically disposed means'.

4. In a variable' load brake rigging fora vehicle truck having a relatively stationary part carried by the truck wheels and also having a part movable vertically relative to the stationary part, in combination, a brake element movable into and out of braking engagement with one of the wheels of the truck, a lever carried by the stationary part of the truck operative for actuating said brake element, a member movable vertically for operating said lever, an arm pivotally carried by a stationary part of the truck for actuating said member, means operative to actuate said arm, said means including a rockable shaft, operative to -actuate said arm, an arm operative to actuate said shaft, a brake cylinder" carried by a stationary part of the truck operative l to actuate the second mentioned arm and adjusting means carried by a stationary part of the truck operative in response to relative vertical'`A 55 movement between the stationary and movable parts of the truck for varying the effective length e of the first mentioned arm.

v5. In a variable load-brake rigging for a truck of the type having a xed part and a part movable vertically relative to the fixed part inV response to variations in the Weight imposed thereon, in combination, a Wheel of the truck, a brake element movable into and out of frictional braking engagement with said wheel, -a lever carried by a fixed part of the vehicle for actuating said brake element, a member movable vertically for actuating said lever, an arm operative for ac#` tuating said member said arm having a longitudinally extending slotted opening, a pin dis-v posed in said slotted opening and movable to dif-` 4 arm for varying the effective length of said arm, rockable means ju the truck foractuating ferent positions relative to the carried by a fixed part of said arm, means operative to actuate saidrockable means and' means associated withl the xed l of the type having a fixed part and a part mov-V able vertically relative to the xed party in response to variations in the Weight imposed there# on, in combinationa Wheel of the truck, 'a brake element movable into and out of frictional brak'- ing engagement with said wheel, a lever carried by a xed part of the'vehicle for actuating said brake element, a member movable vertically for actuating said lever, an arm operative for actuating said member said arm having a longitudinally extending slottedopening, a pin disposed in said slotted opening and movable to diiferent positions relative to the arm for varying the effective length of .said arm, rockable means carried by a fixed part of the truck for actuating said arm, means including a brake cylinder and a brake cylinder lever for actuating said rockable means, and means associated with the fixed and the movable part of the truck and operative in accordance with the load imposed on said movable part for positioning said pin.

- 7. In a variable load brake rigging for a truck of the `type having a iixed part and a part mov able vertically relative to the fixed part in response to variations in the weight imposed thereon, in combination, a Wheel of the truck, a brake element movable into and out of engagement wit/h said Wheel, a pivotally mounted lever dis-v posed longitudinally of the truck for actuating said brake element, `means operative to actuatc said lever, said means including an arm. having a longitudinally extending slotted opening, a pin' disposed in said slotted openingmovable toditferent positions relative to the length ofthe arm for varying the effective length of the arm, vertically disposed means pivotally mounted on an y in combination, a brake element operative for ef-V fecting an application of the brakes, a lever disposed longitudinally of the truck for operating said brake element, a member movable vertically of the truck for actuating said lever, means operative to actuate said member, said means 'including an arm, connecting means operatively connecting said arm and member, said connecting means having a position for providing empty vehicle braking and being movable therefrom to various otherpositions `through a loaded vehicle zone for providing loaded vehicle braking; adjusting means pivotally carried by av stationary part of the truck and `movable in response to relative verticle movement of a movable part of the truck relative to a stationary part of the truck for positioning said connecting means in said loaded vehicle zone.

' 9. In a variable load brake rigging for a vehicle truck of the type having a pair of fixed laterally vspaced side frames with a 'spring plank xed to said side frames and a truck bolster vertically movable relative to the spring plank and the side frames in response to variations in weight imo posed thereon, in combination, a lever pivotally plank operative to vary' the effectivev length of said arm, and means carried by said truck bolster operative. in response to relative lvertical movement between said. springl plank. and thev truck Y bolster' for operating said adjusting-means.

In a variable load brake rigging for a'vehicley truck of ther vtype having a pair of fixed laterally spaced side framesvvitli ai spring plank fixed to said side frames'v Aand a truck .bolster` vertically movable relative to the spring plank and the side frames inresponseto variations in Weight imposed thereon, in combination, a lever pivotally mounted on one of the'side frames and operatively connected to a brake member to be operated for effecting either an application 'or a release .of the vehicle brakes,` a memberv movable vertically for actuating said lever, a rockable arm for operating said member, a shaft rockably mounted on the spring plank for actuating said arm, a brake cylinder carried by the truck side frames for actuating said shaft, a vertically disposed member pivotally carried by the spring plank operative to vary the effective length of said arm, and a roller carried by the bolster` operative in response to relative vertical movement between the spring plank and the bolster for operating said vertically disposed member.

1l. In a variable load brake rigging for a ve hicle truck of the type having a pair of laterally Vspaced lside frames carried. by,V a-v pair oi wheels at each end thereof, 4one-wheel lof each pair. being disposed at one side of the truck and the other Wheel of each pair disposedat the other side of the truck. anda bolster movable vertically relative to the side frames extending transversely of thetruckv and disposed substantially intermediate the ends of said sidey frames, the combination, with a pair of brake elements disposed atl one side of the truck arranged Vone adjacent the Wheel-at one end oft. the-truck andthe other ad' jacent. the wheel at the .other end of the truck and movable into and out of friotional engagement with the adjacent Wheels, of a pair of longitudnally extendinglevers vcarried by the side frame at the same sideof the truck and operative for actuating said brake elements', one of said levers extend-ing from apoint adjacent said bolster ina direction toward one' end of. the truck and the other extending from apoint adjacent said bolster in a direction toward the other end of the truck, a pair of vertically movable members for actuating said levers, an arm operative to actuate said pair of members,v said arm having a longitudinally extending slotted opening, a pin disposed in said slotted 'opening movable to different positions relative to the length of the arm for varying the effective length of said arm, vertically disposed meanspivotally mounted on a part rigidly carried by the side frames and operativei for positioning the pin along they. length of the arm, and means carried by the truck bolster and operative in accordance with the load im" posed on said bolster for effecting operation of said vertically disposed means.

HARRY I. 'mAb/inria. 

